What the Anesthesiologist Should Know before the Operative Procedure

The pericardium has two layers, the visceral layer, which covers the heart and the origin of the great vessels. The parietal layer is reflected off the visceral layer and is a thin layer of fibro-elastic tissue that forms a sac around the heart and separates the heart from the other mediastinal structures. The pericardium contains a small amount of fluid, provides structural support and has a significant hemodynamic effect on the heart. Pericardial diseases may present as congenital defects, pericarditis, neoplasm, and cyst. The etiology of pericardial disease can be classified into the following categories:

Infectious pericarditis

Pericarditis in systemic autoimmune diseases

Type 2 (auto)immune process

Pericarditis and pericardial effusion in diseases of surrounding organs

Pericarditis in metabolic disorders

Previous cardiac surgery

Traumatic pericarditis

Neoplastic pericardial disease

Idiopathic

The perioperative management of patients with pericardial diseases can be challenging due to the diverse spectrum of the etiology and clinical presentation of the diseases. The critical issues for pericardial surgery is the risk for developing or worsening heart failure, cardiac arrhythmias, myocardial infraction, intraoperative major bleeding, abnormal or delayed drug metabolism secondary to multiorgan dysfunction, or can be at risk for developing postoperative respiratory failure.

1. What is the urgency of the surgery?

What is the risk of delay in order to obtain additional preoperative information?

Most cases of pericardial disease requiring a surgical management may follow a long course and do not demand an urgent surgical intervention. Patients with high-risk features of pericardial diseases such as those with significant pericardial effusion or cardiac tamponade should be considered for an urgent surgical intervention.

Emergent:Patients requiring emergent surgery can be hemodynamically unstable. Limited medical history and physical examination should be performed, including of physical signs of significant effusion or cardiac tamponade. Transthoracic echocardiography could be useful in hemodynamically unstable patients.

Urgent:Medical history and physical examination should be performed. The use of limited diagnostics can be considered for these patients.

Elective: These patients are usually hemodynamically stable or have stable, compensated heart failure. There is time for preoperative evaluation including medical history, physical examination, and diagnostics.

2. Preoperative evaluation

The most common medical conditions to evaluate for this procedure are as follows:

Coagulation disorders: history of bleeding or thrombosis, the use of anticoagulants and antithrombotic drugs

Medically unstable conditions warranting further evaluation include: signs of right and left heart failure; pulmonary edema secondary to heart failure.

Delaying surgery may be indicated if: patient is clinically and hemodynamically stable.

3. What are the implications of co-existing disease on perioperative care?

N/A

b. Cardiovascular system

Acute/unstable conditions

Patients with pericardial disease especially those with risk factors for or with a history of coronary artery disease can be at higher risk for the development of acute coronary syndrome, silent myocardial ischemia and congestive heart failure.

Acute coronary syndrome:

High-risk features: accelerated or prolonged angina

Myocardial ischemia without angina may manifest as follows:

General fatigue

Sudden onset pulmonary edema

New onset cardiac arrhythmias

Syncope

Congestive heart failure:

Anxiety

Dyspnoe at rest

Wheezing

Hypotension

Pulmonary edema

Goals of management for these patients include:

Anti-ischemic therapy (beta-blockers in the absence of contraindications, in the presence of contraindications to beta-blockers consider using non-dihydropriridine calcium-channel blockers, ACE inhibitors, i.v. nitroglycerin, i.v. morphine)

Caused by a fixed atherosclerotic coronary lesion. In the absence of an atherosclerotic coronary lesion, coronary artery vasospasm, vascultis, trauma, left ventricular hypertrophy, or aortic valve stenosis can be the causes of myocardial ischemia. Patients with a history of coronary artery disease can be at increased risk for perioperative cardiac complications. There have been several clinical risk factors studied as predictors of perioperative cardiac complications and mortality. Based on the presence and number of these risk factors patients can be stratified into low-, intermediate- and high-risk group categories.

The presence and extent of coronary artery disease in high-risk patients can be further evaluated by non-invasive cardiac stress testing. Based on the findings of a non-invasive cardiac stress test patients with no- or limited stress induced myocardial ischemia can benefit from optimized medical therapy whereas patients with extensive myocardial ischemia should be considered for further evaluation by coronary angiography with a subsequent coronary revascularization.

- Patients with extensive myocardial ischemia should be considered for additional coronary evaluation

Optimized medical therapy:

- Aspirin use

- Beta-blocker use in the absence of contraindications

- In the presence of contraindications to beta-blocker use calcium antagonist or long-acting nitrates

- ACE inhibitor use

- Statin use

c. Pulmonary

COPD:Patients with chronic obstructive pulmonary disease have 2 to 6 time's higher rate of respiratory complications. The higher perioperative incidence of these complications are related to exacerbation of bronchial inflammation as a result of airway manipulation, bacterial airway colonization and surgery-induced immunosuppression.

Reactive airway disease (Asthma):Patients with recent asthma symptoms, patients with current use of anti-asthma drugs and patients with a history of tracheal intubation for severe asthma can be at increased risk for postoperative respiratory complications.

d. Renal-GI:

Implication of renal failure on perioperative care

Avoid worsening of renal failure in patients without end stage renal disease

Patients are often anemic due to decreased erythropoietin production

Increased risk for bleeding due to abnormal platelet function

Peripherial neuropathy and dysfunction of the autonomous nervous system, which results in decreased cardiac response to hypotension

e. Neurologic:

There have been several patient- and procedure-related factors associated with an increased risk of perioperative stroke that may have implication on perioperative care. The risk factors identified for perioperative stroke are as follows:

Preoperative:

- Advanced age, female sex, history of cardiovascular disease

- History of stroke or transient ischemic attack

- Carotid stenosis

- Atherosclerotic disease of the ascending aorta

- Discontinuation of antiplatelet and antithrombotic therapy

Intraoperative:

- High-risk surgical procedures

- General anesthesia

- Duration of surgery, duration of cardiopulmonary bypass

- Manipulation of proximal aortic atherosclerotic lesions

- Cardiac arrhythmias

- Hyperglycemia

- Hypotension and hypertension

Postoperative:

- Heart failure, myocardial infarction, arrhythmias

- Blood loss and dehydration

- Hyperglycemia

The identification and knowledge of these risk factors can facilitate the implementation of diagnostic, therapeutic and procedural measures to modify the risk of perioperative stroke.

f. Endocrine:

Patients with diabetes mellitus can be at increased risk of ischemic heart disease. The risk of perioperative cardiac complications is higher in diabetic patients compared to non-diabetics. Patients with diabetes mellitus are more likely to develop congestive heart failure after surgery than those without diabetes mellitus. Perioperative management of blood glucose levels may be difficult; hyperglycemia has been known to be associated with increased infection rate and delayed wound healing. The use of adjusted doses of insulin based on frequent blood sugar determinations can significantly reduce the risk of mortality and overall morbidity.

g. Additional systems/conditions which may be of concern in a patient undergoing this procedure and are relevant for the anesthetic plan (eg. musculoskeletal in orthopedic procedures, hematologic in a cancer patient)

Hematologic conditions

Preoperative anemia or polycythemia have been shown to be associated with an increased risk of 30-day postoperative mortality. Patients with a preoperative hematocrit levels less than 39% or higher than 51% can be at significantly higher risk of 30-day postoperative mortality and cardiac morbidity. It has been shown that certain high-risk group of surgical patients can be at increased risk of perioperative ischemia and postoperative complications when hematocrit was less than 28%. Increased risk of thromboembolism or hemorrhage has been observed in patients polycythemia, thrombocytosis and other clinical conditions that increase viscosity and hypercoagulability.

Musculoskeletal disorders

Patients with underlying connective tissue disorders are characterized by multiple organ involvement and inflammation. The anesthetic management varies based on the etiology of the connective tissue disorder. Some would require careful airway management, proper positioning, careful titration of anesthetic drugs including muscle relaxants and systemic evaluation for organ dysfunction.

4. What are the patient's medications and how should they be managed in the perioperative period?

Patients undergoing surgical procedures for pericardial disease often have multiple co-morbidities and are polymedicated. As a general rule most of cardiac medications (with few exceptions) should be continued through the perioperative period. A half-life and a dose adjustment of these cardiac medications should be considered according to the patient cardiac condition and of the planned procedure. Other medications taken chronically for other non-cardiac conditions often should also be continued and dose adjustments considered.

Over-the-counter non-steroidal anti-inflammatory drugs can increase the risk of bleeding during surgery. Therefore, it may be best to stop these medications well before surgery.

Herbal medicines may cause problems either through toxicity or through pharmacokinetic and pharmacodynamic interactions. Herbal medicines can have cardiovascular effects, their use can be associated with an increased risk of bleeding or with a prolongation of anesthetic effect. The most commonly implicated herbals and their effects are as follows:

Kava: increases the sedative effect of anesthetic drugs; discontinue more than 24 hours before surgery

Saw plametto: increased risk of bleeding; no data on timing of discontinuation

St John's wort: induction of cytochrome P450 that may affect the metabolism of benzodiazepines; delayed emergence; discontinue at least 5 days before surgery

Valerian: may increase anesthetic requirements; no data on timing of discontinuation

h. Are there medications commonly seen in patients undergoing this procedure and for which should there be greater concern?

Anticoagulant and antithrombotic medication use in the perioperative period are associated with a greater risk of bleeding complications. For patients on vitamin-K antagonists such as warfarin, a heparin substitution is recommended to maintain anticoagulation until the time of surgery.

Antithrombotic and antiplatelet therapy: drugs such as clopidogrel, cilostazol and aspirin should be discontinued 1 week before electice surgery. Patients at high-risk for thrombosis, a substitution with low-molecular weight heparin is recommended to maintain anticiagulation during the perioperative period.

Diuretic use can be associated with serum electrolyte disturbances and should be discontinued a day before surgery.

Potassium supplements can increase the risk of hyperkalemia and should be discontined a day before surgery.

i. What should be recommended with regard to continuation of medications taken chronically?

Cardiac: continue with chronic cardiac medications

Pulmonary: beta-agonist and bronchodilators should be continued in patients with asthma; beta-agonist and atropin analogs should be continued in patients with obstructive pulmonary disease

Renal: discontinue diuretics and potassium supplements 1 day before surgery

Endocrine system: Diabetes mellitus: stop oral antidiabetics and long-acting insulin on the day of surgery; Thyroid: continue with thyroxin; Patients on long-term steroid: continue and consider using a stress dose if the surgical procedure for pericardial disease is planned to be extensive

Psychiatric: antidepressants, neuroleptic drugs, and benzodiazepins; discontinue lithium use 2 to 3 days prior to surgery

j. How To modify care for patients with known allergies -

The most frequently encountered allergies in patients undergoing surgery for pericardial disease are related to antibiotic allergies or allergies to anti-inflammatory drugs. The best medical approach for these patients is to use alternatives to medications to which patients are allergic to.

l. Does the patient have any antibiotic allergies- [Tier 2- Common antibiotic allergies and alternative antibiotics]

The most frequently used combination of antibiotics for surgery of pericardial disease is cefazolin and vancomycin. Beta-lactam allergy patients should get vancomycin as an antibiotic prophylaxis for surgery.

m. Does the patient have a history of allergy to anesthesia?

Malignant hyperthermia

Documented- avoid all trigger agents such as succinylcholine and inhalational agents:

- Proposed general anesthetic plan: patients with a history of malignant hyperthermia (MH) requiring surgical treatment for pericardial disease will benefit from total intravenous anesthesia using a combination of propofol, fentanyl and midazolam. Patients with high-risk pericardial disease such as those with significant pericardial effusion or cardiac tamponade may benefit from etomidate or ketamin induction.

- Ensure MH cart available: [- MH protocol]

Family history or risk factors for MH

Local anesthetics/ muscle relaxants: Local anesthetics that are considered to be safe are lidocaine, bupivacaine, mepivacaine; the use of non-deporalizing muscle relaxant has not been associated with MH.

5. What laboratory tests should be obtained and has everything been reviewed?

Intraoperative Management: What are the options for anesthetic management and how to determine the best technique?

Surgical procedures of pericardial disease are best conducted under general anesthesia with or without regional anesthesia procedures.

Regional anesthesia

There will not be illustrations in this version. There is a spectrum of regional anesthesia procedures that can be considered for surgical procedures of pericardial disease including thoracic epidural, paravertebral, intercostal, and interpleural blocks.

Neuraxial

Benefits: Using these techniques, residual sedative or hypnotic effects of anesthetic drugs can be minimized, early tracheal extubation can be achieved, and the transition to postoperative pain management facilitated.

Drawbacks: some of these techniques may not be used in patients with significant hemodynamic compromise; or in patients with history of heart failure or with significant valvular disease. Patients with chronic anticoagulation may have a relative or absolute contraindication to the use of some of these techniques.

General anesthesia

Benefits: the sometimes extensive and invasive nature of these surgical procedures requires the use of general anesthesia.

Drawbacks: patients with hemodynamic compromise or patients with high-risk pericardial disease can be at significant risk for peri-induction hemodynamic compromise or cardiac arrest

Other issues: maintain adequate preload, maintenance of sinus rhythm, or rate control if sinus rhythm cannot be maintained

Airway concerns: there are usually no specific airway concerns are associated with these procedures.

Monitored anesthesia care

N/A

6. What is the author's preferred method of anesthesia technique and why?

What prophylactic antibiotics should be administered?

A combination of cefazolin and/or vancomycin; in beta-lactam allergic patients vancomycin based on 2010 guidelines.

What do I need to know about the surgical technique to optimize my anesthetic care?

Both median sternotomy and left thoracotomy approaches are used. Left thoractomy approach usually requires ipsilateral lung isolation through a double lumen tube or a bronchial blocker.

What can I do intraoperatively to assist the surgeon and optimize patient care?

Optimized patient care would include appropriate intraoperative monitoring including: arterial line, central line and pulmonary artery catheter. Intraoperative use of transesophageal echocardiography can be of significant help in the assessment of cardiac abnormalities and function. Use of a cell saver is often required given a higher risk of major intraoperative bleeding associated with this procedure. Preparations also should be made for a possible use of cardiopulmonary bypass.

What are the most common intraoperative complications and how can they be avoided/treated?

Myocardial infarction, major intraoperative bleeding, atrial and ventricular arrhythmias, development of heart failure or worsening of the heart failure.

Neurologic: The incidence of perioperative stroke is 0.08% to 0.7% in patients undergoing non-cardiac procedures. The risk of stroke after procedures for pericardial disease can be higher in patients with histories of cardiovascular co-morbidities or in patients whose procedures have to be done on cardiopulmonary bypass. The incidence of stroke for these patients can be as high as 2% to 6%.

a. Neurologic:

Identification of risk factors for stroke can help to implement diagnostic, therapeutic, to procedural measures to modify the perioperative risk of stroke.

Management of the patient's temperature during the perioperative period

Treatment of inflammation and infections

b. If the patient is intubated, are there any special criteria for extubation?

Extubation in the operating room or in the postoperative care unit:

For hemodynamic stable patients with an uncomplicated procedure recovery from surgery can be rapid and there is no requirement for postoperative ventilation

For these patients before extubation normothermia, hemostatis, and hemodynamic stability must be assured

Make sure there is no residual anesthesia/paralysis for long-acting agents

c. Postoperative management

What analgesic modalities can I implement?

Selection of analgesic modalities is best made after evaluation of both patient status and the demands of surgery. For thoracotomy/thoracoscopy procedures a multimodal approach including parenteral opioids, non-steroidal anti-inflammatory drugs, and regional anesthesia can be considered. Several regional anesthesia procedures are available including thoracic epidural, paravertebral, intercostal and interpleural blocks. For procedures through median sternotomy a combination of parenteral opioids and non-steroidal anti-inflammatory drugs can be considered.

What level bed acuity is appropriate?

Appropriate bed acuity should be decided based on patient status, intraoperative course of the procedure and the extent of the performed surgical procedure. Patients with a significant medical history, patients undergoing an extensive surgical procedure or with pre-and intraoperative hemodynamic compromise should get and ICU bed. Patients at low-risk for postoperative complications and with a less invasive procedure should go to a step-down unit.

What are common postoperative complications, and ways to prevent and treat them?

Common postoperative complications for this type of procedure are myocardial infarction, cardiac arrhythmias, respiratory failure and new onset or worsening heart failure. To prevent these complications adequate preoperative risk evaluation should be done to identify patients at increased risk for complications. To prevent cardiac complications one should perform adequate invasive monitoring including arterial line and pulmonary artery catheter. The use of cardioprotective drugs should also be considered including beta-blocker and statins.